You can peruse the lore over at mmosite.com. The Twelve Empyrean Lords were sent forth to defend the Tower of Eternity against the Balaur, warrior members of the original race of Atreia; each one is given a brief description and image. It's evocative stuff, reminiscent of Zelazny's Nine Princes in Amber, the Choirs of the Archangels from the Kabbalah (unsurprisingly) and the kind of radiant archetype seen in anime such as Fate: Stay Night. The images reminded us strongly of Zelazny's Amber Trumps, too; a merchandising opportunity if ever there was one.